UM10503
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User manual
Rev. 1.3 — 6 July 2012
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NXP Semiconductors
UM10503
Chapter 26: LPC43xx Ethernet
[1]
Field is used in version 1. In version 2, messageType field is used for detecting different message types.
There are some fields in the Ethernet payload that you can use to detect the PTP packet
type and control the snapshot to be taken. These fields are different for the following PTP
frames:
•
PTP Frames Over IPv4
•
PTP Frames Over IPv6
•
PTP Frames Over Ethernet
26.7.4.3.1
PTP frames over IPv4
Table 4-6 provides information about the fields that are matched to control snapshot for
the PTP packets sent over UDP over IPv4 for IEEE 1588 version 1 and 2. The octet
positions for the tagged frames are offset by 4. This is based on Annex D of IEEE
1588-2008 standard and the message format defined in
sequenceId 2
30
controlField (
32
logMessageInterva 1
33
Table 580. Message format defined in IEEE 1588-2008
Bits
7
6
5
4
3
2
1
0
OCTETS
OFFSET
Table 581. IPv4-UDP PTP Frame Fields Required for Control and Status
Field Matched
Octet Position
Matched Value
Description
MAC Frame Type 12, 13
0x0800
IPv4 datagram
IP version and
Header Length
14
0x45
IP version is IPv4
Layer 4 Protocol
23
0x11
UDP
IP Multicast
Address (IEEE
1588 version 1)
30, 31, 32, 33
0xE0, 0x00, 0x01,
0x81 (or 0x82 or
0x83 or 0x84)
Multicast IPv4 addresses allowed.
224.0.1.129 224.0.1.130 224.0.1.131
224.0.1.132
IP Multicast
Address (IEEE
1588 version 2)
30, 31, 32, 33
0xE0, 0x00, 0x01,
0x81 (Hex) 0xE0,
0x00, 0x00, 0x6B
(Hex)
PTP-Primary multicast address:
224.0.1.129
PTP-Pdelay multicast address:
224.0.0.107
UDP Destination
Port
36, 37
0x013F, 0x0140
0x013F – PTP event message (
)
0x0140 – PTP general messages